1. Field of the Invention
The present device relates to a positioning device for film mounted in an apparatus which prints an image on the film set to a mount on a photographic printing paper.
2. Description of the Prior Art
Generally, in the case of printing an image formed on a film set to a mount, it is always required to position the film to a certain reference position in an optical printing system, i.e., a position at which, when the film is set, the image on the film can accurately be focused on a photographic printing paper. However, actually, the mounts for the films which are produced by various makers or firms in this art field are different in their thicknesses, respectively, and therefore, the mounts are usually classified into approximately three groups in accordance with their thicknesses. In addition, mount holders to be used also had to be changed everytime when a mount in a different group was used to obviate fuzz or blur of the focused image on a printing paper. In fact, however, it is almost impossible to effect accurate positioning of films in prior art optical printing systems by roughly classifying the mounts, which generally have a wide thickness range of about 1-3.2 mm, only into three groups. Thus, it is considerably hard to completely obviate the fuzz of the focused image on the printing paper. In addition, in a conventional film positioning method, adjustment of curls appearing on the film or reorientation of the film set incorrectly to the mount in an inclined manner cannot be performed.